1. Field of the Invention
The present invention relates to a fly's-eye lens sheet having a light-shielding layer, the fly's-eye lens sheet including a fly's-eye lens sheet body, fly's-eye lenses disposed on one principal surface thereof, and the light-shielding layer disposed on the other principal surface thereof; a method for fabricating the fly's-eye lens sheet; a transmissive screen; and a rear projection image display device.
2. Description of the Related Art
Image display devices in which transmitted light from light sources is modulated by optical elements, such as liquid crystal elements, to display images are known. In such image display devices, external light, such as fluorescent light, present on the side of the viewer is reflected from the display surfaces of the image display devices, resulting in reduction of the contrast of image light and degradation in image quality.
In order to improve the contrast of image light, a method of increasing the intensity of the image light source or a method of reducing reflection of external light in the image display device is employed. In order to display rich color with depth and texture, the latter method, i.e., suppression of reflection of external light, is particularly important.
For example, in rear projection televisions (rear projection image display devices) which have been receiving attention in recent years, transmissive screens are used so as to achieve high transmittance with respect to image light from light sources and to reduce the reflectance of external light, the transmissive screens each having a cylindrical lens on one surface and a light-shielding layer (black stripes) that absorbs external light on the other surface (refer to Japanese Unexamined Patent Application Publication No. 10-293362 (Patent Document 1)).
Furthermore, in order to form a light-shielding layer with high positional accuracy on a cylindrical lens sheet, a method of fabricating a transmissive screen using a photosensitive adhesive layer is known (refer to Japanese Unexamined Patent Application Publication No. 9-120102 (Patent Document 2)). In this method, first, a photosensitive adhesive layer is formed on the viewing surface of a lens sheet. A positive-type adhesive that loses adhesion when exposed to light is used for the photosensitive adhesive layer. A sensitizing source, such as ultraviolet light, is applied from the lens side of the lens sheet to expose the photosensitive adhesive layer. Thereby, the light-collecting portion of the photosensitive adhesive layer is exposed and adhesion is lost. Subsequently, a black layer supported by a support base is bonded to the photosensitive adhesive layer provided with adhesive and non-adhesive patterns, and then the support base is peeled off to transfer the black layer to the adhesive pattern. Thus, a light-shielding pattern with a predetermined shape is formed on the viewing surface of the lens sheet.